Process of making acetates.



11. o.' CHUTE a in?. MQBLROY.

P Bocnss or ummm AGENTES.

firms uAnnY o. CHUTE, orcLEvnn-AND; omo,

DISTRICT F COLUMBIA, ASSIGNORS T0 LIGNO-CHEMICAL COHPAHX, 0I'4 N. Y.. A CORPORATION or NEW Yonx.

P nocnss oF MAKING .AcTArEa To all fwhom it may concern.' 'M

Be it known that We, HARRY O. CHUTE, a :itizen of the'United States, residin in' the 1:ity of Cleveland, in the county o Cuyaloga and State of Ohio, and KARL I. MGEL zoY a citizen of the United States, residing ln' the city of Washington, in' the District of Columbia, have invented certain new and useful Improvements in Processes of MaklngAoetates; and We do hereby declare the following to be a `fullclear, and exact description of the same, such as `Will enable others skilled in the art to which it appertains to make and use the saine. f

l`lThis invention relates to "processes of making acetates and consists inl a method of preparing acetates from the products of the digestion of woody fibers Withalkali by sys. tematically and methodically heating such products under regulated conditions, and in recovering both'theacetate formed and the excess of alkaline reagent; all as'more fully hereinafter set forth and as claimed.

By heating Wood, straw, and other natur'al fibrous materials with an alkali, one of the .first results l'is a splitting of the natural molecules,4 or cdmpound celluloses 'of the to produce cellulose and anothermo! lec-la-rfgroup, orr0ups, uniting with the alkalito forrts'olu Ale products. This is, of' citi'sle, the basis of the ordinary soda pulp ini` u stry,` Bypuson the digestionfurther, as byuse 'of longer igestion, more heat or mOeaIkal, t-h'e yield Aofjlcellulose is lessened and that of these soluble by-products is increased.V In neral therefore in the soda pulp art', the' igestion is pushed only to' the' point where a maximum yield of good clean cellulose results, these soluble by-prod'ctsl heilig ordinarily deemed labsolutely worthless', `a s such.,4 `It is indeed customary to'c'oncentrate the waste lfyt` to a syrup', burnit 4 'daby lixiviation'as carlhe' a ehlH-reislub www? Bpecicatiqnot Lettersjfatent. Patented Aug. A Application filed December 29, 1908. Serial No. :l5-0,4111.

methods, particularly where' some-limited oxidatlon'is allowed, result ln-.lfargersyields estconvenient alkali, and the' Wa'stclyehiiwt convenient form in whichV to io tail'l--thei'ftice? tate formed by its action onflfbefsSuch waste lye will hereinafter therefore bef-generally mentioned lit bein' 'fii'nderstoodthat By pushing the heat'i'jngofjt .e'alkaline lye and contained solublesfurther--th-anwvas done in the digestion@ for-f ellulcsef-the amountof acetate is materiali increased.

ting a limited oxidation.' 'Thisfisl therefore done in the present process,l i .fur-iz.;

Thesyrupy sc da lye aslit leavesltheifiisual vacuum-Leyaporators is the raw-matriellempresent process: The syrupyl'rmssghowever, i't is practically impossible -teLheat smetlidically ,to the necessarygiregulat'ed temperatures because of i-tsplh s '1eal=.consistency. On further heating info p'; 4 gradually from a solution estate offusion of the contained?ssda` salts, .antlfflit is impracticable to handlei't ythrfconveni'ent apparatus, as it gums on stirring-members and bakes on heating niembers;beingzthickf,x4 Yiscid and generally inconvenient-,f1 `=--F uriher after reachln'g-a certaii'vdegree :of delr'ydrw tien it is apt to ignite )Iliuheating'asbycoptact with a spark or aioyelfheatedlsuuiace, burning. away to charcoal-and and even when actual `i 'stlion" oes notitake place, on exposure to` A"e Vaint-fit. '"sgvrylapt to take up' an 4ul'ldue-i?amount@foils o'- en, s ontaneously rise inl-teniperaturuand' ro-4 and especially in the presence ofazanypotash.

To produce maximum .l

generalneeessary'to ex e far-a a, l ciyertingf lient; little-presence of.

:amusementofavsaaeawxygal,.haseen f acetate. But as stated',2soda is thecheajE- e,

other alkaline lyes troni-'fi er mai-bel used. ai?

VA still further yield isobtaine by permit-f played 1x1 the specific embodiment ofslthe.

lili` sodapulp industry is tliechea 'e's'tiandmost' '.chain' This char however is .in anely sub- 'fdivided 4form and in' quite large4 amounti making' the Yextraction A of the acetate; and carbonate rather diicult.

The'v converting operation may-be formed uponthe waste sodalye' under eat pressure in 'closed vessels, the advanta- -geousamount of air.. being pumped into jthe .1 0, the aqueousvapor 'generated `from the ly e to any desired extent and harmful 'omdations can jbe altogether avoided. yIf the Vt e1npjer`a`.turebe rather high, say 150.0 C., l Qn ..remo'val i5-:hashes into steam, andrenders the lye, 1f sufceiitlyeoncentrated originally, ofaLcon- .sistecyadapted td carbonizatlon inf any 'suitablev a "parat'us A Another, and 'preferred method o? eifectin thetmnversmnhowever .2'.0-is t change the'p ysical form .of the lye by i'corprat1ng t a solid, absorbent car- '1' .ier,.:forming` af sort' of vfriable .magma o r -f'solida n'd theni'treat -this mixture -with d1- .to permit the "acetatefforming .oxidation Vwitliiiit vdangferbf ignition or undue oxldationj f. v:

' the lpreferred specificfembodiment of -ltiesfinlsnbsequent lixiviatin. This car- .iei'- h'ouldrbeA substantially un'ailected by the alka1 i,f and-'should be. insoluble;

' atarials.,A Av-certain amount -ofiron ore or aganeseore' is de'eddesirable asiactin ly in vpromoting the formation o 'ftate ii V'd-'e'dtctions,ofr may not. Y', .Sonie little' oxi atioi'n' desirable butA thi s'1as" wiill uen, la jar, ma .-easlv a or' e.` 1n q ya ISlpeHoweve'r, vthe-'labile oxid's, such gQs'andMnOare apparently desir- 1a" artifom their'fsheer oxidizing effect. obtained -f later on is frequently itable asfanabsorbent and .hasmany. ada'i'ta'a'glesi.".l The carrieremployed-should be 1 suc l' amou'nt and of such character` as to i f onvert .theisodaflye into a granular fr iable inass,"-eitherbefore .0r after drying. -Bur'e'iindiluted air should` be excluded oniA the s masa, ,Y 'while under treat-dient to 'pre.entlf for1nation 'of oxalate's'and destrucfti nfof' acet'ates. i 'Atmospheres of various indiiferen't'gases and 'mixtures may be emg'. and lin; .th

from thelboilergthe 'water present l the syrupy soda waste -lye Charbraize, coke Tandiron ore are suitable f 'some' way"`1rot understoodQ-Thisj ion "'n'ay. be due 1tje, alternate oxidatlor'is and4 i e preliminary or convertl the "limited oxidation deemed des1r able.

They, have'fthe further advantage Vof quickly converting-'any caustic 'alkali present in the lye into carbonate= Excess .of caustic alkali tends to produce marsh gas 4from acetates by f a well known reduction. lAs issu-in from 'vessel The air so introduced 1s diluted by? afboiler 4 furnace, products of com uston vabout the right-temperature for dryingand converting-the soda waste lye. From a well managed boiler` furnace the wastes. gases leave at about-200 C. j

The lye as absorbed in the ulverulent or granular carrier may be first ried and then heated by direct exposure` to gasesfroma boiler furnace, admixed with additional air pause at about 150 C. maximum production of acetate, that alwater" after this treatment, while; the acetate may beregained from the solution'by crystallization orother means, such extraction eyer, the oxidationis4 pushed in the conversion stage, the easier such extraction becomes. Therefore unless by-products are to after this operation', such materialg :fp ref- "erably' .next '"Acetat'ef ofsodium above, without much loss whi e the other organlc Abodies present are not -so resistant,

most part. If therefore theconverted mass benext. carbonized .auor about these'ftelnper- 'methodically operating apparatus-like .the vordmary diffusion battery, .the .carbonate leaching;- -Returned-char used-as an 'absorbent givesfa harder` char,

-.hwever, than the .char aaorded by" .1 ea ng soda waste lye carbonized 1w* atures," a mass is obtained which. consists.

and, acetate arel dissolved, 4leaving the :char v and absorbent behind. -It is in "this operation that a hard granularabsorbent ofth'e. 4

nature of coke ,is particularly'-useful as -fa-" eilitating leaching. 'The natural "charof the. carbon-ized mass while .sometimes'hard and' resistant' .is oftener disintegrated"ging thev of the mass 'i have the' additional advantage of being# 5 vao or not as .their compositionmay indicate, bring'Ing-it'slowly up to a temperature bef tween 110O and 200; preferably with some v This'results'in aA read present -in theA soda vwaste lyev being' is nevertheless diiicult, The further, how- -be regained, which maybe done by solution and fractionalA treatments of thematerial is a tolerabl'y stable saltand stands temperatures up to 400 C., and .perha s somewhat becoming carboni'zed' 'at ab0`11t400? for the 115.. mixed with char and with the absorbent better. .suited-.for

fii "talli'lzationffmay be burned to regain carl, A E the pump and a source osfnprodu'cts sel 1lscreened; anular coke, free from dst`, nia`y used-afan absorbent inthe :treatment of "lye,A carried through the Vrecess-to the leaching and then returned ""5 or re-use. Lighter-,softer particles of car- V'bon resulting `rom the charring of the l 'e Acan,otten*befsifted away from the co 'e particleslf AS methodical .burning will also remove them. However, the char formed 10,upontcokeyfsometimes has enough body to warrantfits re-usefTheisiftingm elutriates orrothjerchar separilted from the coke, wherel coke is or f tlie'lexcess char when 'char a eturned`,fshoul d ordinarily' be 1 egain'thesoda carried; Itis subially'ilpracticable and not particularly u var 1ta'geo`us 'towleach to complete 'extraction 'n of salts, so' that some is ordinarily i leftin'theleached material. Separation' of $---the acetate'Y "and carbonate in the leached somfaybeV by fractional lcrystalbln.` *l "`"'1hei' are'I several expedients which ma yin fthe recnrer1 of the acetate wi advantagefwhen desired. `One of these is to take thehotcarbonized mass',l prior to leach rig,s"prinlle itwi'th water to' cool and hycombustion to convert thecar- 'atefinto bicarbonate. By then leaching y Ilires, moet of the bicarbonate is left behind in fthe Char andthe acetate solution formed relatively pure. y The bicarbonate, l35 canthen be leached out with hot water, or

' 'thencbaif ash and thewarbonate.

aa1a.e.

when -,operating with soda ul" ,lye, all the-sdium carbonate regained un 4@various operations should be caustidaUt bfk .t0 the Pulp mill An advantageous method ofl operating is ',tggleachthe carbonizcd mass with hot water,

c .extrat-ingLeverything soluble. Hot Water ,-5 `gives y ytelex-ably Afcirmentrated solution v and v,good yextaction. From this solution, the

" te., n carbonate may be directly sepaf .by fractional crystallizationin well rstcod'ways 0r, the solution may be l onate, and then fractional cr stallization'practicedg Mother liquors a er crys- 01 ty este a 'screw at `its lower.

and then@ subject to `a'current of cool all" amountsof water at ordinary" ,g products of combustion tngwipnatemost ofthe carbonate as bi ca Asorbent is deliveredint'o a conduit-5,pro-

vided with a screw conveyer carrying "breaking and mixing blades at its'upper end and v y This completes the mixture and-perfecte the absorption. From 70 the conduit the mixture,l which 4should `be d riable and granular, isseht intof converting-` apparatus 7, which, as shown, lconsists of a lrotary cy1inder,driv en by ear 8 and housed by end; casings-Q-and' 10. he former is 'provided with a valved Hue 1l leadingjto -a' stack. The latterv is provided with a conduit -12 receiving material Afrom the rotaryl converter and provided" with "a valve 13 and door 14 permitting removal of converted material prior tocarbonization if so desired. Downwardly the conduit leadsin'to' ,a'carbonizen indicated as a Lwholelbyf'lll".

This vcal-bonizer, as shown,is set at-an angle andlcontans'the drag -conveyer"15'. #A `8'5 nace l'sends4 heat through ilue 17,i5the''eby heating thel carbonizer above said llue. The flue leads to stack 18.- From the carb'niiei the material is fed'b gate 19` into conduit'l 20, also provided wit .a `breaking conveyer. `9`0 Pipe 21 allows wetting the material immedi `ately upon vexit from the carbonzer." From this conduit, the cooled materialmay beifed into eitherxof thefdiagramkmaticallyshown,1 leachers 21. Pipe 40 allows introduction 95 of products ofcombustion. l

` `To securethe necessary conditions, there mal and chemical, inthe rotary converter,

the latter is provided with a pipe `22'fed` by n blower 23 from the chimney stack and there- 100 by adapted' to introduce products of `combusv tion in regulated amount.A Connected tothis pipe is `a valved steam pipef24.' lOn the suction side of the fan is a valved inlet 25pol'` A mitting introduction of regulated amounts 105 of cold'airQ-'Pipe 26, communicat `with' stack heater 27 permits introduction of heated air. Q- Connecting with" the stackL is shown Yfragmentarily an ordinary'boiler 28,AL i .provided with steam dome l29 and' valved 110 outlet pipe 30 leading into the carbonizer. Soda pulp waste lye may be boiled down in this boiler and led directly to the carbonizer; A high pressure [pump '31V and pipe 32 `r- Init introduction of a certain amount o airy or air mixed with "products of combustion into the boiler vagainst the steam' ress ure to aid in oxidation, as, described.` nduit valved at 36 offers communicationbetweem ,fcqmr 12o llYVSi-l'ilie Amma n www .new into the converte v regulated heat and oxidation 'by the current ofl boiler gases.' With lthe rotary converter shown, a greater or less speed of rotation corresponds Vto a greater or less forward progress of the material therethrough and control of the time of eX osure to the heat is, consequently afforded. peed of feed of the y converter at the much above 100 1 reachesabout 200 with boiler'gases. lBy

slow rotation and feed, the higher temper- .ature is pushed backward toward the entrance and conversely. The 'heat .ofy the boiler ses can be tempered as much as may i be desired -bythe steam. For'present purposes, both steam and boiler gases act alike, both diluting whatever air may be' present. Boiler gases with ordinary firing usually contain aslmuch excess airas is necessary,

but withinore carefuliring, usin less ex-jy cess of air under the grate, it is requently desirable .to introduce a little hot or 'cold air. With careless firing,y it is sometimesl better to dilute the products of combustion further with somesteam. For the present urpose of course, ordinary boiler gases may deemed diluted air being a mixture of. -Y more or less-unchanged combustion. p

It is usually desirable to run the greater part of the converter at an average temperatureof about 150. Thermometric obsery air with products of vations= may be madev through the pluggedV )rifice A'mixture lof air and inert gases corresponding to 10 to 20 per cent; airis a suitable atmosphere to be' used in the converter, the higher the average heatxthe more dilute .being -the air. It is not necessary to `run the 'converter' with; air tight housings, which adds to the convenience of the apparatus shown, but there' should bey a slight lenum therein to insure that'leakageshall be outward. 'In the `carbonizer'the temperature at the lower end should not exceed 400. C. as a rule, Athough 10 or 20 degrees excess do no eat harm. Oxidation 4is not necessary or esirable hereand no gas troducin means are shown. Some ga evolved Y vides a suitable atmosphere, bein nonavzri, dizin'g. -It escapes upward throug the feed conduit and mixesharmlessly with the products ofI combustion. Q

' 'The apparatus 'shown may be used to Lprov duce acetate directly from woody fibersieyglthf` out employ' soda waste lye as agrawmaterial. For. is pur ose, saw-dust;` comminuted straw or the ike may be soaked in,

I -this asa raw material, acetateis alkali solution and introduced through hoppers ,4 and 3 into `the apparatus. 'Us

to a large extent at the of cellu- 1n 'the carbonization and this PIQL lose portion of the Woody molecules,ias well as at that of the i no-cellulose; the portion extracted by s a in makingsoday pulp.

With such fibers used' directly, Vthe 4fiberv itself acts as an absorbent.

What weV claim is: l f1. In thel manufacture of acetates, the process which-consists in first producing an alkali solution of woody-fiber constituents, then absorbing the same in an absorbent material and oxldizing the mass while in a heated state4 by meansof diluted air.

2. In the manufacture of acetates, the process which consists in producing an alkali solution of woody-fiber constituents, absorbing the same in an absorbent material and oxidizing the mas's while in a heated state by means `of air diluted with products of' combustion.' p

` 3. In the manufacture of acetates, f the -process which consists in producingv an alali solution Vof woody-fiber constituents,

oxidizing the-'mass while in a heated state by diluted air and carbonizing by a higher heat out of contact with. air.

4. In the manufacturer of acetates, thel process' whichconsists in.' producing an alali solution o f woody-fiber constituents,

absorbing the same inzan absorbent material, oxidizing the mass While 'in aheated state by diluted air, carbonizing by a higherkheat out of contact with 7air, and separating the carbonate and acetate of alkali from the car- -bonized mass. Y

5. In the manufacture of v acetates, the process which consists inpassing arvvgranulated mass of alkalized woody-fiber constituents past a current of hot diluted air, traveling in the ,o osite `direction, the temperature of said diluted air and the amount'of i oxygen therein being controlled to causev formation 'of acetates. i

y 6. ,In the -manufactur'e Vof` ace-tates, the process which consists in absorbing an alkaline solution of woody-fiber constituents in anpabsorbent to produce 'a 'granulary mass and passing said nular mass past a current-.of-hot'dilut air, traveling in the opfansite direction, the'temperatu're of said div. luted air and the amount of oxygen therein controlled to cause ,formation oface- 7. In the manufacture rocess which consists in-absorbing an alkaline solution of woody-fiber vconstituents' inl an absorbent to 'roduce af`granular mass, passing said gran ar mass past a current Vof hot diluted air' and carbonizing Lby a .higher heat out `of contactwith air.

8. In Ithe manufacture ofacetates, processwhich consists 'in mixin waste soda gulp lye with a "granular absor nt to prouce a granular'm'ass, and pa 'Y ,said Agranular v.mass past .a current of hot uned absorbing the same in. an absorbent material,

vof acetates, the

Lair,4 traveling in the op osite direction, the

temperature of said diluted air and the 4amount of oxygen therein' being controlled tofcause formation of acetates.

9. In the manufacture of acetates, the process whichl consists 1n mixing Waste soda `pulp lye with a granular absorbent to pro duce a granular massypassing said granular mass past a current of hot diluted air and corbonizing out of contact with air.

l10. In the manufacture of' acetates, the process which consists 1n mixing waste soda pulp lye with a granular absorbent to pro-r duce a granular mass, passing said granular mass through a rotary cylinder While in contact with a heated atmosphere containingl products of combustion and airwand 'carbonizin out of contact with air.'

11. In't e manufacture of acetates, the

4process which consists in mixing Waste soda ,woodytiber constituents combined with alkali by means of diluted air and then carbonizing out of contact with air.

13. In the manufacture of acetates, the' process which consists in oxidizing heated soda waste lye by diluted air and then passing the oxidized material continuously down a heated conduit out of contact with external air. y y

14. In the manufacture of acetates,` the vrocess' which consists in drying and heating soda waste :lye to an acetate forming temperature out of contact with pure air and in then carbonizing out of contact lwith air. v

t l 15. In the manufacture of acetates, the

process which comprises absorbing soda Waste lye in an absorbent material and sub?.

ject-ing the mass to the oxidizing action of diluted air at acetate forming temperatures.

In testimony whereof we aiiix our signatures in the presence of tWo Witnesses.

H. O. CHUTE.

K. P.' MCELROY.`

Witnesses: I C. W. FoWLR, Armario M. HoUGH'roN. 

